Why Do Not Track faces an uphill road

March 4, 2013, 11:45 AM UTC

FORTUNE — Legislation to give Internet users the right to prevent advertisers from tracking their online activities was re-introduced in the Senate on Thursday. It has little chance of passing.

The proposed Do Not Track Online Act sounds a lot like the very popular federal Do Not Call legislation that was passed a decade ago, creating a registry where people can enter their phone numbers to be screened out of receiving obnoxious telemarketing calls.

Even though online tracking by advertisers is potentially much more of an intrusion on privacy, there is very little in the way of a groundswell of support for legislation restricting it, as there was for the Do-Not-Call Implementation Act of 2003. That’s because whereas telemarketing calls involve annoying, disruptive phone calls, online ad-tracking takes place behind the scenes, often entirely unbeknownst to Internet users. And since it doesn’t disrupt anybody’s day, people are much less likely to complain about it even when they know the details. Also, many people like having advertising aimed particularly at them, and personalized ads help finance free Web sites.

The legislation is sponsored by Sens. Jay Rockfeller (D-W.Va.) and Richard Blumenthal (D-Conn.). It would allow users to opt in to a browser setting that would tell third parties, usually advertisers, not to track their browsing activity. Tracking enables advertisers to target ads at specific users based on their online activities.

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The ad industry insists that data is collected anonymously (individual computer addresses are tracked but not names or other personal information), and the industry has been stalwart in opposing legislation restricting it. Last year, advertisers pledged to work to come up with a solution that would allow users to opt out of tracking, but so far, no such solution has been forthcoming. Hence the re-introduction of the bill. Advertisers have “failed to live up to that commitment,” Rockefeller said in a statement on Thursday.  “My bill gives consumers the opportunity to simply say ‘no thank you’ to anyone and everyone collecting their online information. Period.”

The bill would give enforcement power to the Federal Trade Commission and state attorneys general. The ad industry has argued that the industry should be allowed to police itself, though it hasn’t yet come up with a mechanism for doing so. The legislation faces tough opposition from industry lobbyists, and given the relative lack of public clamor, it seems likely at this point that it will get very far.